Hi,
I have base model M1 Ultra 20 Cores 64 GB RAM 48 GPU and 2TB SSD. I have been using this one since july 2022.
It is copmletely inaudible during ZBrush/C4D Modeling, Shading or Look Dev. You can not hear any fan noise while working with Photoshop/Illustrator or Corel Painter.
Even in all day long 3D rendering sessions it is inaudible. You can feel it is warm when you touch the M1 Studio chassis only during this 3D rendering sessions. Other wise it is cold and there is no fan noise.
Please do not buy M1 Max on Mac Studio, even 64 GB RAM with it is not enough for apps which uses multithread cores like ZBrush.
I have experienced both Max and Ultra. There is a lot difference on Photoshop and Corel Painter (for hi res files) and ZBrush/C4D Blender. If you use Corel Painter for Hi Res workflow don't even think to buy M1 Max Studio.